During use of an electronic apparatus incorporating a substrate on which electronic parts are mounted, especially a mobile device such as a mobile phone having high portability, a user may drop involuntarily this electronic apparatus. When the mobile device drops and hits against a floor surface, a motherboard incorporated in the mobile device may be significantly distorted, and the electronic parts on the motherboard may be separated therefrom. Thus, the electronic parts used in the mobile device are required to ensure peeling strength withstanding the distortion of the motherboard caused by a drop impact.
A mechanism of the separation of the electronic parts due to the distortion of the motherboard is that the electronic parts are not distorted even though the motherboard is distorted, stress thereof concentrates on a terminal connecting the electronic parts and motherboard, whereby the terminal or a portion around the terminal is damaged. On the basis of the mechanism, as a method of enhancing the peeing strength, there is a method that reduces rigidity of the electronic parts so that the electronic parts easily follow the distortion of the motherboard. In a module including a resin substrate, electronic parts mounted on the resin substrate, and a shield case disposed on the substrate so as to cover the electronic parts, the rigidity thereof is determined by a structure of the shield case, so that it is possible to enhance the peeling strength by optimizing the structure of the shield case.
The following Patent Document 1 discloses a shield case formed into a box-like shape and one end being opened having a top plate and side plates, and put on a substrate housed in a casing of an electronic apparatus in such a manner that opened edges of the side plates are brought into contact with a ground pattern formed on the substrate. In this shield case, a plurality of slits are formed so as to face the opened edge of each side plate and to divide the side plate into a plurality of sections.